Sodium & Blood Pressure
Nearly all Americans ingest too much salt each day. For many people, the more salt consumed, the higher their blood pressure. Decreasing salt intake is recommended to reduce the risk of high blood pressure. High blood pressure increases the chances of having a stroke, heart disease and kidney disease.
High blood pressure is a heart risk. Changes in daily habits can prevent or delay the onset of high blood pressure, as well as lower blood pressure if it is already too high. To maintain a healthy blood pressure or lower a high blood pressure, it is important to take these five actions:
- reducing salt intake;
- increasing potassium intake;
- losing excess body weight;
- increasing physical activity; and
- eating an overall healthful diet.
A diet rich in potassium lowers blood pressure. Potassium blunts the effect of salt on blood pressure. Fruits and vegetables are rich potassium sources. Some examples are leafy green vegetables, sweet potatoes, white potatoes, tomato paste, carrots, bananas and dried fruit. Dairy products, meat and cereal products are also good sources of potassium.
Chemically, salt is sodium chloride. The U.S. Dietary Guidelines recommend eating less than 2,300 milligrams (mg) of sodium per day. In fact, it is recommended that those with high blood pressure or those at high risk (due to family history) consume only 1,500 mg per day. This is a challenge in the United States because we eat so many processed foods, which are usually high in sodium. Many of us have also learned to enjoy salty foods.
Losing weight, increasing activity and eating a healthy diet are important to successfully lowering blood pressure. Take care of yourself, because high blood pressure can sneak up on you! Be sure to note your blood pressure during doctor's visits and ask what the numbers mean. There are two numbers in a reading: a top number and a bottom number. The top number, called the Systolic, should never exceed 140. The bottom number, called the Diastolic, should never be more than 90. According to the American Heart Association, it is ideal to have a Systolic number of 120 or less, and a Diastolic number of 80 or less.
The nutrient panels on food labels list sodium content, not salt. Foods that are low in sodium have 140 mg of sodium or less per serving. Some foods can have more than 900 mg of sodium in one serving. The foods that commonly have high sodium contents are processed entrees, snack foods and canned soups. Avoid all foods with high sodium content.
Look for foods that have less than 300 mg of sodium per serving. Nutrition facts labels will show you how much sodium is in the food per serving.
Eat the following foods very rarely, if ever:
- salted crackers, chips, pretzels
- cereals with more than 300 mg sodium per serving
- canned vegetables that contain salt ("no salt added "canned vegetables or rinsing canned vegetables are both acceptable)
- sauce packets with frozen vegetables and Ramen noodles
(Note: It is often less expensive to buy frozen vegetables without added sauces. Ramen noodles contain at least 1,600 mg of sodium in a one block of noodles! If you read the label, it says that each package is two servings, but most people will eat the whole package as one serving and ingest more sodium in one meal than they should have in a single day. If you eat Ramen noodles, don't use the whole package of flavoring-use a small portion of the season packet, or don't use any at all.)
- smoked meats
- bacon, ham and sausage
- canned meats
- frozen foods high in sodium (such as prepared dinners)
- bouillon cubes (use reduced-sodium)
- barbeque sauce, catsup, Worcestershire sauce, soy sauce, miso
- pickles, olives, relish
- canned and frozen soups high in sodium
A Note About Sodium and Lithium
The whole nervous system needs salt (sodium). Lithium is a naturally occurring mineral with an electrical charge similar to salt. The level of salt in your body affects the action of lithium. Once lithium reaches therapeutic range, it can be altered by small changes in daily salt intake.
If you normally don't eat much salt and then sit down one night and eat a bag of potato chips or a pizza or canned soup, your lithium level will likely decrease. If you've been diligent with your lithium medicine routine but have changed your salt-eating pattern, it may significantly interrupt your medication treatment outcome. Keeping your sodium intake fairly consistent is very important for people who take lithium.
If you are very active and sweating a lot, or have diarrhea or are vomiting, you could lose a lot of sodium and then your body may end up with too much lithium. Never take salt tablets or go on a salt-restricted diet without talking to your doctor if you are taking lithium. Lithium has predictable blood levels, and to understand what is too high or too low, talk with your health care provider about adjusting your lithium dosage if you are lowering your sodium intake.